The death of Jolee Mohr, the Illinois woman who developed a massive and fatal infection while testing a gene-therapy drug from Seattle-based Targeted Genetics, will get its first full public airing Monday at a meeting hosted by national health authorities.
While experts don't expect the session to completely solve the mystery, many will be watching.
If the anti-arthritis drug the 36-year-old woman helped test is ultimately held responsible, there could be severe implications for the company and the promising but controversial field of gene therapy.
It's the first time since Mohr's July 24 death that all the clinical data about her and the fungal infection that likely led to her death will be presented, with company executives, Mohr's doctors and researchers from the National Institutes of Health and the Food and Drug Administration attending.
But Targeted Genetics Chief Executive H. Stewart Parker said there will be no conclusive data to provide a final verdict on whether the company's drug was responsible for weakening Mohr's immune system, allowing the infection to take over.
The company says there's no evidence from clinical and preclinical trials that the drug could have contributed to the immunosuppression.
Dr. Kyle Hogarth, the University of Chicago Medical Center doctor who treated Mohr at the intensive-care unit where she died, said this week it's too early to rule out the drug's role.
He said the meeting, at the National Institutes of Health campus in Bethesda, Md., will help steer further research, which relies on limited tissue and blood samples.
The meeting "will actually be quite productive," he said.
More complete conclusions from the data being studied by Hogarth and other researchers in Chicago could be available in three to four weeks, officials said.
Mohr's death clouded hopes for the future of gene therapy, a field already tainted by the death of 18-year old Jesse Gelsinger during a University of Pennsylvania experiment in 1999.
Gelsinger died of an immune reaction to an adenovirus used to transfer disease-fighting genes into his cells. In the aftermath of his death, many gene-therapy experts pinned their hopes on adeno-associated viruses (AAVs), known to be much milder.
AAVs are the core of Targeted Genetics' pipeline. The FDA, which suspended the Targeted Genetics trial after Mohr's death, said it was stepping up monitoring of other studies pending investigation.
Over 600 patients in 29 FDA-supervised trials have been treated with AAV-related therapies.
The Targeted Genetics drug was designed to deliver a gene that weakens the immune response in joints affected by arthritis, reducing inflammation. The AAV vector is supposed to stick to the area where it's injected.
Mohr's case is complicated. The herpes virus was present in her body, and she had been exposed to another arthritis-fighting drug that suppressed the immune system, said Hogarth.
But if University of Chicago researchers conclude that Targeted Genetics' AAV spread beyond Mohr's knee, where it was injected, or that the gene carried by the AAV virus was active in other parts of her body and contributed to the general failure of her immune system, the effect could be chilling on all AAV-related research.
Some experts think that's unlikely. "My suspicion is that this is not related to the vector," said Mark Kay, a gene-therapy expert at Stanford University. "But again, I hate to jump to conclusions either way."
The timing of Mohr's fatal illness, which came shortly after a second dose of the drug was injected, make it difficult to discard the therapy as a culprit, said Hogarth.
Alan Milstein, the attorney who represented the Gelsinger family and now represents the Mohrs, will attend the Bethesda meeting, along with Jolee Mohr's husband.
Milstein said Mohr's death underscores the extreme risk of gene-therapy clinical trials, especially when they're performed on nonterminally ill patients.
Monday's meeting will be webcast live by the NIH at www4.od.nih.gov/oba/RAC/meeting.html.
Ángel González: 206-515-5644 or agonzalez@seattletimes.com
